Department of Pharmacy and Pharmaceutical Technology, School of Pharmacy, University of Santiago de Compostela, Avda. de las Ciencias s/n 15782 Santiago de Compostela, Spain.
J Biomed Nanotechnol. 2009 Apr;5(2):162-71. doi: 10.1166/jbn.2009.1017.
The purpose of this work was to develop a new type of nanoparticles made of PEG-grafted chi-tosans (CS-g-PEG) using tripolyphosphate (TPP) as a polyanionic crosslinker and to investigate the potential of these nanostructures as gene carriers. The formation of these nanoparticles was optimised by the evaluation of the combined effects of pH, PEGylation degree and chitosan/crosslinker ratio on the particle formation. The selected CS-g-PEG/TPP nanoparticles were studied with regard to their physico-chemical properties, DNA association efficiency as well as to their toxicity and gene expression in vitro. Furthermore, the best performing nanoparticle prototypes were also evaluated for their potential for in vivo gene delivery. CS-g-PEG/TPP nanoparticles displayed a high DNA association efficiency combined with high stability and low cellular toxicity. The results of the in vitro transfection assays showed positive effects of the PEGylation in the case of particles prepared from high molecular weight chitosan, while the presence of PEG slightly decreased the efficiency of the nanoparticles based on low molecular weight chitosan. Overall, high and long lasting gene expression levels could be observed for all types of nanoparticles. Moreover, CS-g-PEG/TPP nanoparticles also mediated high gene expression levels in vivo, following nasal administration. These results indicate the potential of ionically crosslinked CS-g-PEG/TPP nanoparticles as transmucosal gene delivery systems.
本工作旨在开发一种新型纳米粒子，该纳米粒子由聚乙二醇接枝壳聚糖（CS-g-PEG）组成，使用三聚磷酸钠（TPP）作为多阴离子交联剂，并研究这些纳米结构作为基因载体的潜力。通过评估 pH 值、PEG 化程度和壳聚糖/交联剂比对颗粒形成的综合影响，对这些纳米粒子的形成进行了优化。研究了所选的 CS-g-PEG/TPP 纳米粒子的物理化学性质、DNA 结合效率以及体外毒性和基因表达。此外，还对最佳性能的纳米颗粒原型进行了体内基因传递潜力的评估。CS-g-PEG/TPP 纳米粒子具有高 DNA 结合效率，同时具有高稳定性和低细胞毒性。体外转染实验的结果表明，对于由高分子量壳聚糖制备的颗粒，PEG 化具有积极的作用，而 PEG 的存在则略微降低了基于低分子量壳聚糖的纳米粒子的效率。总体而言，所有类型的纳米粒子都能观察到高且持久的基因表达水平。此外，经鼻给药后，CS-g-PEG/TPP 纳米粒子还介导了体内的高基因表达水平。这些结果表明离子交联的 CS-g-PEG/TPP 纳米粒子作为黏膜基因传递系统的潜力。
